Fixture



FIXTURE Filed Feb. 22, 1944' MWA` 22 l la e9 22 la I9 I 48 57.2'6-.4

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Patentecl July 1, 1947 UNITED STATES PATENT OFFICE FIXTURE William C. Williams, Santa Monica, Calif.

Application February 22, 1944, Serial No. 523,414

(Cl. T7-62) 4 Claims.

My invention relates to a fixture or jig and has particular reference to an adjustable fixture by means of whichholes may be accurately drilled in a workpiece or other machining operations performed thereon at substantially any'desired angle to the principal planes thereof This application is a continuation-impart application of my copending application Serial No 444,537, led May 26, 1942, now abandoned, and entitled Drill jig.

In certain manufacturing industries such as, for example, the aircraft manufacturing ind-csd try, certain of the fabricating or assembling cperations require that one or more holes be drilled through or into a workpiece at certain angles to the surface of the workpiece other than perpendicular thereto and with the normal plane including the axis of such inclined hole extended in a particular direction with respect to the shape or form of the workpiece. This is particularly true in the aircraft industry where the holes employed to receive the rivets, bolts or other attaching means in the framework of the plane or in the skin sheets attached to the framework need to be disposed at odd angles in order to permit the rivet, bolt or the like to be passed through the hole.

The drilling of such holes presents a considerable problem particularly where it is desired to incorporate the drilling operation into a mass production schedule. It is the present practice to provide for the proper location and angular disposition of these holes by using a xed drill axis and mounting the workpiece upon an adjustable table, the ordinary drill press with an adjustable table representing a typical example of the mechanism used to drill such inclined holes.

This mode of drilling the holes has certain disadvantages, not the least of which resides in the fact that the workpieces must be placed on the table before the hole can be drilled and must be removed from the table before a similar op eration can be performed upon another piece. This entails a great deal of effort and a considerable loss of time where the wor-kpieces corn prise large sheets or prefabricated structures of considerable size. There is encountered, furthermore. the diiculty of positioning such larg sheets or pieces of mechanism on the support .ing table of the drill press with sufficient accuracy to insure the proper location of the lho-le in such workpiece.

In certain industries and particularly in the aircraft industry the present practice is to uset in preference to the drill press mentioned in the preceding paragraph, fixed drill guide jigs which are adapted to be temporarily secured or clamped to the workpiece in the desired location so that a hand supported drill usually electrically or air driven may be employed for drilling the hole, the jig including a drill guide which serves to permit the operator of the drill to hold the drill in the desired angular position.

While these jigs operate satisfactorily as to the drilling of a particular hole, it is obvious that a separate jig of this type is required for each different size of hole to be drilled or for each dierent angle of inclination of the hole. Furthermore, if for any reason the plans and specifications are so changed as to call for a different size of hole or ardiiferent angle of inclination of the hole, the fixed type of drill jig must be discarded and a new one constructed to take its place. It is an object of my invention to provide a fixture of the character set forth in the preceding paragraphs which includes a novel locking mechanism for holding the parts immovable in any adjusted position in which they may be placed.

It is a still further object of my invention to provide a drill guide which includes an adjustable means for readily and accurately positioning a drill guide of substantially any selected size at substantially any desired angle relative to the origin of pre-established reference axes of a workpiece.

It is also an object of my invention to provide a drill guide of the character set forth in the preceding paragraph which provides a means for readily and accurately positioning the axis of the drill guide at any desired angular inclination from the normal to the surface of the workpiece.

It is an additional object of my invention to provide a drill guide of the character set forth in the preceding paragraphs which includes a means for accurately disposing the normal planeincluding the drill guide axis at any desired angle to the reference axes of the workpiece.

Other objects and advantages of my invention will be apparent from a study of the following specifications, read in connection with the accompanying drawings, wherein:

Fig. l is a top plan view of a xture or drill jig constructed in accordance with one embodiment of my invention and intended particularly for use in guiding drills employed to drill holes at an an- 3 gle inclined from the normal to the workpiece in which such hole is to be drilled;

Fig. 2 is a cross sectional view taken substantially along the line II-II of Fig. 1 and illustrating the relative positions of the parts of the device illustrated in Fig. 1 when that device is adjusted to provide for the drilling of a, hole in a direction normal to the surface of a workpiece upon which thedevice is placed;

Fig. 3 is a cross sectional View similar to Fig. 2 but illustrating the relative positions of the parts of the device when those parts are adjusted tol incline the axis of the drill guide from the normalto the surface of the workpiece;

Fig. 4 is a fragmentary sectional View4 taken substantially along the line IAV-IV ofV Fig. l, and

illustrating the details of construction ofV a locking mechanism employed to lock one of thel protractor setting rings employed on the device; and

Fig. 5 is a fragmentary sectional view taken substantiallyl along the line V-V ofA Fig. 1 andl illustrating the details of construction of a friction device employed toV produce a predetermined amount of frictional resistance to rotation of one of the protractor'members.

Referring tot the drawings, I- have illustrated in Fig; 1 oneV phase ofmy invention as embodied in an adjustable drill guideintended tofb-e employed for the purpose of guiding. drills to be used for the drilling ofV holes through a workpiece when those holesareinclinedvf'romanormal tothe surface of such workpiece.

In Fig'. 1 the workpiece-is indicated generally by the reference character` IY and the adjustable drill guide device isindicated generally by the reference character 2. This device comprises areetangular base member 3 including longitudinal indexv lines l and/or index holesv 5 by means of which the device may be longitudinally aligned with a longitudinalreferenceline B: inscribed or otherwise suitably marked on the workpiece I and representing one ofl theaxes of the-hole whichA is to be drilled` in the workpiece I'. Similarly, the base member 3 may include-transversely extending index lines or marks 'I permitting the device as a whole to be aligned with transversely extending reference lines 8v also7 inscribed on the workpiece- I and employed to define theV other axis, ofv the holeftobe drilled in the-workpiece.

Generally speaking, the device of my invention includes, in addition to the' base member 3, an outer adjustable protractor ring 9 concentrically positioned with respect to a vertical line or axis Iii which is positioned-normally with respect to an undersurface I-I- of the base-member 3 and. passes through the intersection of the index linesi and '1. Within the protractor ring 9 there is mounted an outerrotatable member I2, this member being concentrically positioned with respect to the axis I and supported for-rotation. thereabout by the base member 3.

Thev outer member I2` in turn rotatably supports an inner rotatable member I3', this latter member being supported for rotation about an axis I4 which is inclined at an angle w to the axis Ill, the axis I4 being' so positioned as to intersect the axis I3 at the point of intersection of the axis I'EJWith the undersurface I I of the base member 3, such point of intersection being indicated in Fig'. 2 by the reference character El.

The inner rotatable member i3 is in turn bored as at I to receive any one of a plurality of drill guide members IG, each of such members It being identical with the others except for the` diameter of the drill guiding aperture i'I which is defined 4 by the drill guide I6, the guiding aperture I1 of each of the members I6 corresponding to the different sizes of drills with which the guide is to be used.

The axis of the drill guide receiving bore l5 is inclined from the axis I4 of the member I3, this latter angle of inclination being also preferably equal to the angle of inclination w of the axis I4 withrespect to the axis I0 and like the axis Iii also intersects the axis I@ and the axis Iii at the intersection of these axes with the undersurface of' the base member 3.

The protractor ring 9 may be rotatably supported upon the base member 3 as by providing inthe base member an annular upwardly facing groove. I3 which is formed in the upper surface of the base member 3. The ring 9 may include a lower guiding portion I9 (see Fig. 4) contoured to conform to the conguration of the annular groove I8 so as to beY received within said annular' groove and guided thereby. for rotation about the axis I0. The member 9- also preferably includes an upwardly extending iiange-like portion 23 defining an outer surface 2I which may be knurled or otherwise adapted for grasping with the ngersy to permit the member 9. to be turnedA tol any desired angular positionv aboutthe axis Iii.

I have found it desirable torimpose a certain amount of frictional-l resistance to the turning of the member 9 as thisappears to, aid in the accurate. setting of thismember to a desired angular position. Accordinglyy theouter-periphery of the guiding portion I9 isr provided with a circumferentially extending. groove 22 dimensioned to loosely receive-the edge or a clampingv Washer 2-3, which washer isy in turn positioned. inv a suitably contouredl recess 24` formed in the upper'surface of thel base, member., 3'. The recess 24. is preferably formed with av depth such as to position the bottoml of the recess somewhat4 below the lowermost surfacev of the slot- 22. An adjustingscrew 25 is threaded into a suitably threaded bore 2t formed` iniy the base member 3, the screw' 25 be.- ing passed through a suitable aperture formed in the clamping Washer 23.

A spring member 21 comprising preferably a conventional type of spring lock washer is interposed between the headA of the screw 25 and the upper surface of the clamping washer 23. By this means an adjustable downwardly directed spring pressure may be exerted on the clamping washer 23.V so asto force-the portion I9 of the protractor member 9. into pressure engagement with the bottom of the recess I8 within which that portion is received to thus impose an adjustable frictional resistance to the turning of the member 9.

As is clearly'shown in Fig. 4, I' provide a smilarly constructed mechanism for locking the member 9 against further movement after it has once been rotated to thev desired adjusted position. This locking mechanism may include a lockingy plate or washer 28 received in a suitable recess 29 formed in the upper surface of the base member 3 and so positioned as to extend the edge of the washer 28 into the locking groove or channel 22 which is formed in the member 9. A thumby screw 3B is threadedly engaged with the base member 3 and passed through a, suitable aperture formed in the locking platev 28 so that by merely tightening the locking screw 3U with the lingers, suiiicient pressure may be exerted on the member 9 to securely lock the same against rotation.

The member 9 preferably also includes an inclined or sloping upper surface 3| which is graduated as is indicated at 32 in Fig. 1, these graduations preferably being in terms of degrees so that the angular position of the outer protractor member 9 with respect to the index lines 4 and 1 may be ascertained by having reference to an index plate 33 (see Fig. l) which includes an in.. dex 34 aligned with the longitudinal index lines 4. The index plate 33 may also include Vernier type graduations 35 to provide additional accuracy in the reading and in the' setting of the angular position of the member 9.

The aforementioned upwardly extending flange portion 20 of the member 9 is preferably cut away for a portion of its circumference to terminate at points identiiied by reference characters 36 and 31 in Fig. 1. Between these two points there is inscribed along the upper edge of the sloping surface 3| a second index 38 and vernier calibrations 39 to coact with a suitable angular calibration 40 inscribed on a protractor ring 4| secured to the periphery of the outer rotatable member I2.

The index 38'is preferably positioned in coincidence with the 90 mark of the protractor ring 32 so that the angle indicated by the index 34 and the calibration 32 represents the angular position of the index 38 with respect to the transverse lines 1. Thus the member 9 constitutes an adjustable index plate by means of which the index 38 for the protractor scale 49 may be moved to any desired angular position with respect to the transverse index lines 1.

Attention is directed to the contour of the inner surface of the member 9 which provides an annular space for receiving the protractor ring 4I. This protractor ring includes a sloping upper surface 42 upon which the protractor scale 40 is inscribed and includes also a horizontally positioned undersurface 43 which overlies a horizontal upper surface 44 defined by the guiding portion I9 of the protractor ring member 9 so that the protractor ring 4I serves to confine the portion I9 within its guiding annular recess I8. The protractor ring 4I may, if desired, be formed integrally with the member I2 but is preferably formed as a separate piece secured to the member I2 in a suitable manner as, for example, by means of welding 45.

Reference has hereinbefore been made to the fact that the outer rotatable member I2 is supported by the base member 3 for rotation about the vertical axis IIJ. This supporting of the member I2 is accomplished by forming the member I2 with a downwardly extending cylindrical bearing portion 45 which is closely received within a suitably sized aperture 41 extended through the base member 3 and disposed concentrically relative to the axis IIJ.

Means is preferably provided for locking the outer rotatable member I2 in any position in which it may be placed. Such a locking means may comprise, as is illustrated in Fig. 2, a locking screw 48 threadedly engaged with the base member 3 and positioned in such location as to engage a conical point 49 formed thereon with a suitably contoured and suitably positioned annular recess 59 formed in the periphery of the cylindrical portion 46 of the member I2.

vA similar arrangement is employed for rotatably supporting the inner rotatable member I3 on the outer member I2, the inner member tatable member I2.

including a cylindrical portion 5l which is closely received Within a suitably sized aperture 52 extended through the member I2, the aperture 52 being concentricwith and aligned with the aforementioned axis I4. A locking arrangement similar to that previously described for the member I2 may also be employed for the member I3, this latter locking arrangement comprising a locking screw 53 threadedly engaged with the member I2 in a position to dispose the conical end 54 of the screw 53 in a suitably contoured and suitably positioned annular recess 55 extended circumferentially about the cylindrical portion 5I.

The inner member I3 includes a head portion 56 which is in turn for-med with a sloping skirt-like portion 51. The sloping surface 51 is preferably calibrated in degrees as is indicated at 58 in Fig. 1, these calibrations being intended to coact with a suitable Vernier type index plate 59 secured to the upper surface of the outer ro- The head portion 55 of the inner member I3 denes also a plane upper surface 60 which is disposed normal to the axis of the drill guide receiving aperture I5 so that the enlarged head portion 6I of the drill guide I6 may be seated on the surface 60.

Each of the drill guides I6 is preferably removably secured to the inner member I3 when placed in operative position therein so as to prevent upward movement of the member IB during the time the drill is being used and also prevent rotation of the drill guide member I6 wit in the drill guide receiving bore I5 as a result of the frictional engagement of the rotating drill with the drill guiding aperture I1. Accordingly, I provide a shoulder screw 62 which includes a threaded shank portion screwed into the upper plane surface B9 of the inner member I3 and which includes also a cylindrical shoulder portion 64 having a diameter somewhat exceeding the diameter of the shank portion and including also a head portion 65 of cylindrical form having a diameter somewhat exceeding the diameter of the shoulder 64. The side surfaceof the head portion Blof the drill guide I6 is preferably cut away as is illustrated in Fig. 1 to form a partially cylindrical axially extending groove 6B to receive the head 65 and permit the drill guide I6 to be moved longitudinally in the bore I5 past the screw 62. l

The cut away portion of the head 6I serves also to define a radially extending flange B1 adapted to pass beneath the head 65 so that by inserting the drill guide in the bore I5 to permit the screw head 65 to pass along the channel 66 and by then turning thedrill guide I5, the flange 61 may be caused to pass under the head 65 and prevent upward movement of the guide.

The cut away portion of the drill guide termi-l nates in a shoulder 69 adapted to bear against the head 65 and prevent rotation of the drill guide.

Fig. 3` illustrates the same structure as is illustrated in Fig. 2 but shows the parts turned to extend the axis of the drill guiding aperture l1 at an angle 0 to the vertical axis I9, Fig. 3 illustrating the special case where the parts are in such position as to make which is the maximum amountJ of inclination which may be imparted tothe axis of the drill guiding aperture I1.

It will be noted that the magnitude of the angle a fis pontrolgled :by the-angular position of.. thener;` member I3 with respect tothe outerv member I 2'; I't-will` be further/noted thaty the-angular positionof; theouter rotatablefmember I2 vcontrols or.; determinesthe. angular relation between thelongitudinal-.index linesV `l -and the-Vertical plane dened; bythe vertical'I axis- I0. and the sloping axisofitheldrill'guidingaperture- I'I. The relation betweenthese angles may -be expressed. as follows:

sini

sin w of inclination of the-axis-IA with respect to the axisI-,and also the-.angleof inclination of the axisfofy the drill guiding aperture. I'I-with respect `11o-,the axis lI 4;

Similarly,- the horizontal. ang-le through whichthe outer rotatable fpart-l2must `bemoved fromthe initial position -illustratedinFigs.- 1 and 2 to produce :coincidence between the index lines Vil and-*the- Vverticalplane deiined bythe l sloping axis.l of'A the -drillguidingapert-ure I "I- andthe verticaLaXis I 0 is represented-by cos1wfsin-2- where and-thaw.; are` asabove-defined and a represents the tangle-through which the member I 2= isto.-.be rotated fromY the-initial.9 position illustratBd-in vF'ig,. 1.-

Inftheevent itris Vde sired `tofposition the ver-y tical. pla-ne which includes the inclined axis-of the-drill; guiding aperture. II at somev angular'V position: other than in coincidence-with'the index linesy-IIy/it ismerelyynecessaryto first set' the' outer/protractor ring vto a position-indicating lonV the-index -34.- thedesiredangularl location ofY the-aforementioned fvertical plane. The protractorfring -9 may thenfbe'lockedinfsuch posif tion by means of the locking screw 30, whereupon the youter member I2 is-turned to` indicate, by means ofthe-protractor scale duron-the index'38, the determined'value oftheangle a and the outer memberv-is -thenlockedfin'such adjusted position byf-:meansof the locking screw 43; The inner member lis-fthen rotated to a position in which theaprotractor'scale 53 indicates onv the index plane` 59th'e determinedvalueV of the anglewhereupon the inner member is locked in such position by means of the locking screw-53.? This operation serves to position the axis of the drill guiding aperture I'I at the desired angle of inclination. with: respect -to'r the vertical` axis' VI 0' and serves.: also to vextend the nVertical .plane which' includesfthe axisfofithe drillv guidingeperture I'I4 itx-the desired' directionwith respectfto the index IBCSZ:

Il; will be understood, ofcourse-,that in order for the hole which may be drilled by using the drill guide thus positioned to pass through the desired ilocation; represented .byy the intersection of the-.axes IiV Tand 8;.'it is necessary that.: the base member 3 be positioned as illustratedy infiFig. 1 withthelindexdinesfscoincidingwith the. marks 6 .andwithI the. indexlines 'l coinciding with the marks 8. Under ordinary circumstances thebase plate .3 will-be securedto the .workpiece .I insuch position. as-.by means of asuitablehold-down clamp or other securing device.

The mode-of operation. of the mechanism. may be perhaps .more clearly illustrated. .by consider.- ing certain vspecific ,examples Example #1 Assume that itis desired to drill a hole .throughr the-'workpiece rI at ani-angle of `20? fromithe ver.-

tical: and-that the-vertical .plane rwhichiincludesthe axis fof. vthe hole .be vextended at an anglefof 45 measured in a:icountercloclmvisedirectiony tol the. index-lines Il.: Assume further, that thedevice is. so constructedthat the anglewfis equalto 15'.

This setting-ofthe, device Amay befiaccomplished bly-flistrturningrthe. protractor ring 9 to. a position such that `the desired angle of 45 is -indicated''byftl'ie'scafle'l 324 at the index SII.: The pro-y tractorfring :iris theirlocked in'. this position by means'of the thumb screw 30.1'

By means of: Equation 2;'the angle afor 0:20"

The inner member I3,is -thenrotated to a position in which'theascertained'angle of l84 17"is indicated byr'the-calibrations l'oppositethe index 59 and the inner member isi lockeddn this position by means of the locking sarei/V53.y

Havingfmadefthese adjustments to the members 9; I2'and I 3 the angle of 'the drill guidingaperture I'! 'is positioned atan-inclinationpf 20 from the vertical axis I0 and the vertical. plane` including the drill guiding axis is positionedat an angleof 45 With-respect to they longitudinal index lines 4.

Example #2 Assumel that it: isv desired `to .so,1adjust.V thedevice that the holeicontrolled by; thefdrillY guide I @will beinclined from-the verticalat an-angle: of

5 and that the direction of this4 inclination -will1 be at right angles to ylongitudinal; indexf-lines'fa' Assume also, as in Example #1', thatthe angle-wf isequalto v15"'. The outerprotractor ring 9'fis turned to arposition indicating the. desiredright' ianglerelationship by a reading onfthe scale ,32"

opposite vthe index'3ll'fandthe thumbscrew 3011s employed to locky the protractor ring!!V in'thaty position.l

From Equation Z'aboVetheangle a correspond'- ing to 0:5", w=15 is ascertainedl to be 80 371 The outer rotatable member I2is turnedto aposition such that the ascertainedl'angle of 80;

37 is indicated by the scale` dflon theindex 38and the locking. screw 48is employed to lsecure the outer member I2 in that position.

0=5, w`=15 is found to be 19 24'. The inner rotatable member E3 is turned to a position suchv that the ascertained angle of 19 244 isv indicated by the scale 58' opposite the index Eiland the inner member i3 is locked in that position by` the screw 53'. This operationserves to dispose the axis of the drill guiding bore II'in a positionv corresponding to. the. above noted assumed desired position.'v

Thereafter by means.l of. 'Equationfl Vthe angle* e corresponding.

From Equation 1 above the angle 4 correspondingto.

From the foregoing, it will be observed that I have provided a novel fixture which, as described by the presently preferred embodiment of my invention, may be used to position a drill guide so that the axis of the hole drilled and guided by the device may be positioned as desired, extended at any desired inclination relative to the vertical and inclined at any desired direction relative to reference lines marked on the workpiece and identifying the desired surface location of the hole.

Attention is further directed to the fact that with respect to the form of the invention just described, it is important that the parts be so arranged that the axes ld, I4 and the axis of the drill guiding aperture I1 all intersect each other at the point l) positioned in the plane defined by the under surface H of the base member 3. By so arranging the axes, the possibility of the hole location being shifted by making adjustments to the amount or direction of the inclination of the hole is avoided. l

While I have shown and described the pre ferred embodiment of my invention, I do not desire to be limited to any of the details of construction shown or described herein, except as dened in the appended claims.

I claim:

1. In a fixture, the combination of: a base member having an undersurface adapted to be placed in contact with a workpiece; an outer member mounted for rotation on said base member about an axis intersecting said undersurface, said outer member having a hole extending therethrough at an angle to said axis of rotation such that the axis of said hole intersects said axis of rotation at the point of intersection of said axis of rotation with said undersurface; an inner member mounted for rotation in said hole, said inner member having an aperture extended therethrough; and a tool guiding member mounted in said aperture and dening a guiding line disposed at an angle to said axis of rotation such that said guiding line intersects both of said axes at said point of intersection of said axes with said undersurface.

2. In a fixture, the combination of: a base member having an undersurface adapted to be placed in contact with a workpiece; means on said base member dening a pair of vertical index planes intersecting each other to define a reference point on said undersurface; an outer member mounted for rotation on said base mem ber about one axis passing through said reference point; an inner member mounted on said outer member for rotation about another axis disposed at an angle to said one axis and passing through said reference point; and a tool guiding member mounted on said inner member and dening a guiding line disposed at an angle to said other axis of rotation and passing through said reference point.

3. In a fixture, the combination of: a base member having an undersurface adapted to be placed in contact with a workpiece; means on said base member dening a pair of vertical index planes intersecting each other to dene a reference point on said undersurface; an outer member mounted for rotation on said base member about one axis passing through said reference point and disposed at right angles to said undersurface; an inner member mounted on said outer member for rotation about another axis disposed at an acute angle to said one axis and passing through said reference points said inner member having a drill guide receiving bore formed therein in such location that the axis of a selected drill guide placed in said bore extends at an acute angle to said other axis of rotation and passes through said reference point.

4. In a iixture, the combination of: a base member; a protractor ring mounted for rotation on said base member; means on said base member dening an index cooperating with said protractor ring; an outer member mounted for rotation on said base member concentrically with said protractor ring, said outer member having protractor graduations inscribed 0n its outer periphery; another index means carried by said protractor ring in a position to cooperate with said graduations on said outer member; an inner member mounted on said outer member for rotation about an axis disposed at an angle to the axis of rotation of said outer member; protractor means associated with said inner member and with Vsaid outer member for measuring the angular position of said inner member relative to said outer member; and a tool guiding member mounted on said inner member and defining a guiding line disposed at an angle to the axis of rotation of said inner member.

WILLIAM C. WILLIAMS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,092,867 Sellew Apr. 14, 1914 512,545 Gilman Jan. 9, 1894 809,432 Darrschmidt Jan. 9J 1906 FOREIGN PATENTS Number Country Date 65,176 Switzerland July 31, 1913 

